PHP commit_sql函数代码示例

 /**
  * Ends a (possibly nested) transaction.
  */
 static function finish_transaction()
 {
     self::$transactions--;
     if (self::$transactions == 0) {
         commit_sql();
     }
 }

/**
 * Remove stale context records
 *
 * @return bool
 */
function cleanup_contexts()
{
    global $CFG;
    $sql = "  SELECT c.contextlevel,\n                     c.instanceid AS instanceid\n              FROM {$CFG->prefix}context c\n              LEFT OUTER JOIN {$CFG->prefix}course_categories t\n                ON c.instanceid = t.id\n              WHERE t.id IS NULL AND c.contextlevel = " . CONTEXT_COURSECAT . "\n            UNION\n              SELECT c.contextlevel,\n                     c.instanceid\n              FROM {$CFG->prefix}context c\n              LEFT OUTER JOIN {$CFG->prefix}course t\n                ON c.instanceid = t.id\n              WHERE t.id IS NULL AND c.contextlevel = " . CONTEXT_COURSE . "\n            UNION\n              SELECT c.contextlevel,\n                     c.instanceid\n              FROM {$CFG->prefix}context c\n              LEFT OUTER JOIN {$CFG->prefix}course_modules t\n                ON c.instanceid = t.id\n              WHERE t.id IS NULL AND c.contextlevel = " . CONTEXT_MODULE . "\n            UNION\n              SELECT c.contextlevel,\n                     c.instanceid\n              FROM {$CFG->prefix}context c\n              LEFT OUTER JOIN {$CFG->prefix}user t\n                ON c.instanceid = t.id\n              WHERE t.id IS NULL AND c.contextlevel = " . CONTEXT_USER . "\n            UNION\n              SELECT c.contextlevel,\n                     c.instanceid\n              FROM {$CFG->prefix}context c\n              LEFT OUTER JOIN {$CFG->prefix}block_instance t\n                ON c.instanceid = t.id\n              WHERE t.id IS NULL AND c.contextlevel = " . CONTEXT_BLOCK . "\n           ";
    if ($rs = get_recordset_sql($sql)) {
        begin_sql();
        $tx = true;
        while ($tx && ($ctx = rs_fetch_next_record($rs))) {
            $tx = $tx && delete_context($ctx->contextlevel, $ctx->instanceid);
        }
        rs_close($rs);
        if ($tx) {
            commit_sql();
            return true;
        }
        rollback_sql();
        return false;
        rs_close($rs);
    }
    return true;
}

//.........这里部分代码省略.........
    $rs = get_recordset_select('dialogue_conversations', 'grouping != 0 AND grouping IS NOT NULL', 'dialogueid, grouping');
    $dialogueid = 0;
    $grouping = 0;
    $groupid = null;
    $inconversation = array();
    $newusers = array();
    while ($conversation = rs_fetch_next_record($rs)) {
        if ($dialogueid != $conversation->dialogueid || $groupid != $conversation->groupid || $grouping != $conversation->grouping) {
            if ($dialogueid == 0 || $groupid === null) {
                $dialogueid = $conversation->dialogueid;
                $groupid = $conversation->groupid;
            }
            $cm = get_coursemodule_from_instance('dialogue', $dialogueid);
            $context = get_context_instance(CONTEXT_MODULE, $cm->id);
            $users = (array) get_users_by_capability($context, 'mod/dialogue:participate', 'u.id, u.firstname, u.lastname', null, null, null, empty($groupid) ? null : $groupid, null, null, null, false);
            $managers = (array) get_users_by_capability($context, 'mod/dialogue:manage', 'u.id, u.firstname, u.lastname', null, null, null, null, null, null, null, false);
            $dialogueid = $conversation->dialogueid;
            $groupid = $conversation->groupid;
        }
        if ($grouping != $conversation->grouping) {
            if ($grouping) {
                if ($userdiff = array_diff_key($users, $inconversation, $managers)) {
                    foreach ($userdiff as $userid => $value) {
                        $newusers[$userid . ',' . $grouping] = array('userid' => $userid, 'courseid' => $cm->course, 'grouping' => $grouping);
                    }
                }
            }
            $inconversation = array();
            $grouping = $conversation->grouping;
        }
        $inconversation[$conversation->recipientid] = true;
    }
    if (!empty($dialogueid)) {
        // Finish of any remaing users
        $cm = get_coursemodule_from_instance('dialogue', $dialogueid);
        $context = get_context_instance(CONTEXT_MODULE, $cm->id);
        $users = (array) get_users_by_capability($context, 'mod/dialogue:participate', 'u.id, u.firstname, u.lastname', null, null, null, empty($groupid) ? null : $groupid, null, null, null, false);
        $managers = (array) get_users_by_capability($context, 'mod/dialogue:manage', 'u.id, u.firstname, u.lastname', null, null, null, null, null, null, null, false);
        if ($userdiff = array_diff_key($users, $inconversation, $managers)) {
            foreach ($userdiff as $userid => $value) {
                $newusers[$userid . ',' . $grouping] = array('userid' => $userid, 'courseid' => $cm->course, 'grouping' => $grouping);
            }
        }
    }
    rs_close($rs);
    if (!empty($newusers)) {
        foreach ($newusers as $key => $newuser) {
            begin_sql();
            course_setup($newuser['courseid']);
            if ($conversations = get_records('dialogue_conversations', 'grouping', $newuser['grouping'], 'id', '*', 0, 1)) {
                $conversation = array_pop($conversations);
                // we only need one to get the common field values
                if ($entry = get_records('dialogue_entries', 'conversationid', $conversation->id, 'id', '*', 0, 1)) {
                    unset($conversation->id);
                    $conversation->recipientid = $newuser['userid'];
                    $conversation->lastrecipientid = $newuser['userid'];
                    $conversation->timemodified = time();
                    $conversation->seenon = false;
                    $conversation->closed = 0;
                    $conversation = addslashes_object($conversation);
                    if (!($conversationid = insert_record('dialogue_conversations', $conversation))) {
                        rollback_sql();
                        continue;
                    }
                    $entry = array_pop($entry);
                    $srcentry = clone $entry;
                    unset($entry->id);
                    $entry->conversationid = $conversationid;
                    $entry->timecreated = $conversation->timemodified;
                    $entry->recipientid = $conversation->recipientid;
                    $entry->mailed = false;
                    $entry = addslashes_object($entry);
                    if (!($entry->id = insert_record('dialogue_entries', $entry))) {
                        rollback_sql();
                        continue;
                    }
                    $read = new stdClass();
                    $lastread = time();
                    $read->conversationid = $conversationid;
                    $read->entryid = $entry->id;
                    $read->userid = $conversation->userid;
                    $read->firstread = $lastread;
                    $read->lastread = $lastread;
                    insert_record('dialogue_read', $read);
                    if ($entry->attachment) {
                        $srcdir = dialogue_file_area($srcentry);
                        $dstdir = dialogue_file_area($entry);
                        copy($srcdir . '/' . $entry->attachment, $dstdir . '/' . $entry->attachment);
                    }
                } else {
                    mtrace('Failed to find entry for conversation: ' . $conversation->id);
                }
            } else {
                mtrace('Failed to find conversation: ' . $conversation->id);
            }
            commit_sql();
        }
    }
    return true;
}

/**
 * Ensure all courses have a valid course category
 * useful if a category has been removed manually
 **/
function fix_coursecategory_orphans()
{
    global $CFG;
    // Note: the handling of sortorder here is arguably
    // open to race conditions. Hard to fix here, unlikely
    // to hit anyone in production.
    $sql = "SELECT c.id, c.category, c.shortname\n            FROM {$CFG->prefix}course c\n            LEFT OUTER JOIN {$CFG->prefix}course_categories cc ON c.category=cc.id\n            WHERE cc.id IS NULL AND c.id != " . SITEID;
    $rs = get_recordset_sql($sql);
    if (!rs_EOF($rs)) {
        // we have some orphans
        // the "default" category is the lowest numbered...
        $default = get_field_sql("SELECT MIN(id)\n                                    FROM {$CFG->prefix}course_categories");
        $sortorder = get_field_sql("SELECT MAX(sortorder)\n                                    FROM {$CFG->prefix}course\n                                    WHERE category={$default}");
        begin_sql();
        $tx = true;
        while ($tx && ($course = rs_fetch_next_record($rs))) {
            $tx = $tx && set_field('course', 'category', $default, 'id', $course->id);
            $tx = $tx && set_field('course', 'sortorder', ++$sortorder, 'id', $course->id);
        }
        if ($tx) {
            commit_sql();
        } else {
            rollback_sql();
        }
    }
    rs_close($rs);
}

 /**
  * Restores the data in the question
  *
  * This is used in question/restorelib.php
  */
 function restore($old_question_id, $new_question_id, $info, $restore)
 {
     $status = begin_sql();
     $minfo = $info['#']['MATRIX'];
     $newmatrix = (object) array('questionid' => $new_question_id, 'grademethod' => backup_todb($minfo[0]['#']['GRADEMETHOD']['0']['#']), 'multiple' => backup_todb($minfo[0]['#']['MULTIPLE']['0']['#']), 'renderer' => backup_todb($minfo[0]['#']['RENDERER']['0']['#']));
     $newmatrix->id = insert_record('question_matrix', $newmatrix);
     $rows = $minfo[0]['#']['ROWS'][0]['#']['ROW'];
     // why does this get eaten?!
     $rowmapping = array();
     foreach ($rows as $row) {
         $row = $row['#'];
         // more nonsense
         $newrow = (object) array('matrixid' => $newmatrix->id, 'shorttext' => backup_todb($row['SHORTTEXT']['0']['#']), 'description' => backup_todb($row['DESCRIPTION']['0']['#']), 'feedback' => backup_todb($row['FEEDBACK']['0']['#']));
         $status = $status && ($rowmapping[backup_todb($row['ID']['0']['#'])] = insert_record('question_matrix_rows', $newrow));
     }
     $cols = $minfo[0]['#']['COLS'][0]['#']['COL'];
     // why does this get eaten?!
     $colmapping = array();
     foreach ($cols as $col) {
         $col = $col['#'];
         // more nonsense
         $newcol = (object) array('matrixid' => $newmatrix->id, 'shorttext' => backup_todb($col['SHORTTEXT']['0']['#']), 'description' => backup_todb($col['DESCRIPTION']['0']['#']));
         $status = $status && ($colmapping[backup_todb($col['ID']['0']['#'])] = insert_record('question_matrix_cols', $newcol));
     }
     $weights = $minfo[0]['#']['WEIGHTS'][0]['#']['WEIGHT'];
     foreach ($weights as $weight) {
         $weight = $weight['#'];
         $newweight = (object) array('rowid' => $rowmapping[backup_todb($weight['ROWID'][0]['#'])], 'colid' => $colmapping[backup_todb($weight['COLID'][0]['#'])], 'weight' => backup_todb($weight['WEIGHT'][0]['#']));
         $status = $status && insert_record('question_matrix_weights', $newweight);
     }
     return $status && commit_sql();
 }

 /**
  * Adds a new document or updates an existing one. The necessary set_ 
  * methods must already have been called.
  * @param string $title Document title (plain text)
  * @param string $content Document content (XHTML)
  * @param int $timemodified Optional modified time (defaults to now)
  * @param int $timeexpires Optional expiry time (defaults to none); if
  *   expiry time is included then module must provide a 
  *   modulename_ousearch_update($document=null) function
  * @param mixed $extrastrings An array of additional strings which are
  *   searchable, but not included as part of the document content (for
  *   display to users etc). This can be used for keywords and the like
  * @return True for success, false for failure
  */
 function update($title, $content, $timemodified = null, $timeexpires = null, $extrastrings = null)
 {
     global $OUSEARCH_NO_TRANSACTIONS;
     if (empty($OUSEARCH_NO_TRANSACTIONS)) {
         begin_sql();
     }
     // Find document ID, creating document if needed
     if (!$this->find()) {
         // Arse around with slashes so we can insert it safely
         // but the data is corrected again later.
         if (!empty($this->stringref)) {
             $beforestringref = $this->stringref;
             $this->stringref = addslashes($this->stringref);
         }
         $beforeplugin = $this->plugin;
         $this->plugin = addslashes($this->plugin);
         $ok = insert_record('block_ousearch_documents', $this);
         if (!empty($beforestringref)) {
             $this->stringref = $beforestringref;
         }
         $this->plugin = $beforeplugin;
         if (!$ok) {
             debugging('Failed to add ousearch document');
             if (empty($OUSEARCH_NO_TRANSACTIONS)) {
                 rollback_sql();
             }
             return false;
         }
         $this->id = $ok;
     }
     // Update document record if needed
     if ($timemodified || $timeexpires) {
         $update = new StdClass();
         $update->id = $this->id;
         if ($timemodified) {
             $update->timemodified = $timemodified;
         }
         if ($timeexpires) {
             $update->timeexpires = $timeexpires;
         }
         if (!update_record('block_ousearch_documents', $update)) {
             debugging('Failed to update document record');
             if (empty($OUSEARCH_NO_TRANSACTIONS)) {
                 rollback_sql();
             }
             return false;
         }
     }
     // Delete existing words
     if (!delete_records('block_ousearch_occurrences', 'documentid', $this->id)) {
         debugging('Failed to delete occurrences for ousearch document ' . $this->id);
         if (empty($OUSEARCH_NO_TRANSACTIONS)) {
             rollback_sql();
         }
         return false;
     }
     // Extra strings are just counted as more content in the database
     if ($extrastrings) {
         foreach ($extrastrings as $string) {
             $content .= ' ' . $string;
         }
     }
     // Add new words
     $result = $this->internal_add_words($title, $content);
     if (empty($OUSEARCH_NO_TRANSACTIONS)) {
         commit_sql();
     }
     return $result;
 }

                            $resp_txt = new Ejercicios_texto_texto_resp(NULL, $id_pregunta, $resp_textarea, 0);
                            $resp_txt->insertar();
                        }
                    }
                    echo "insertado";
                }
            } else {
                if ($tipo_origen == 4) {
                    // ES UNA IMAGEN
                    if ($tipo_respuesta == 1) {
                        //La respuesta es un texto
                        //$preg = required_param('pregunta' . $j, PARAM_TEXT);
                        $preg = "foto_" . $id_ejercicio . "_" . $j . ".jpg";
                        $ejercicio_texto_preg = new Ejercicios_texto_texto_preg(NULL, $id_ejercicio, $preg);
                        $id_pregunta = $ejercicio_texto_preg->insertar();
                        $ejercicio_texto_img = new Ejercicios_imagenes_asociadas($NULL, $id_ejercicio, $id_pregunta, $preg);
                        $ejercicio_texto_img->insertar();
                        $num_resp = required_param('num_res_preg' . $j, PARAM_INT);
                        for ($k = 1; $k <= $num_resp; $k++) {
                            $resp_textarea = required_param("respuesta" . $k . "_" . $j, PARAM_TEXT);
                            $resp_txt = new Ejercicios_texto_texto_resp(NULL, $id_pregunta, $resp_textarea, 0);
                            $resp_txt->insertar();
                        }
                    }
                }
            }
        }
    }
}
commit_sql();
redirect('./view.php?id=' . $id_curso . '&opcion=9');

/**
 * Marks user deleted in internal user database and notifies the auth plugin.
 * Also unenrols user from all roles and does other cleanup.
 * @param object $user       Userobject before delete    (without system magic quotes)
 * @return boolean success
 */
function delete_user($user)
{
    global $CFG;
    require_once $CFG->libdir . '/grouplib.php';
    require_once $CFG->libdir . '/gradelib.php';
    require_once $CFG->dirroot . '/message/lib.php';
    begin_sql();
    // delete all grades - backup is kept in grade_grades_history table
    if ($grades = grade_grade::fetch_all(array('userid' => $user->id))) {
        foreach ($grades as $grade) {
            $grade->delete('userdelete');
        }
    }
    //move unread messages from this user to read
    message_move_userfrom_unread2read($user->id);
    // remove from all groups
    delete_records('groups_members', 'userid', $user->id);
    // unenrol from all roles in all contexts
    role_unassign(0, $user->id);
    // this might be slow but it is really needed - modules might do some extra cleanup!
    // now do a final accesslib cleanup - removes all role assingments in user context and context itself
    delete_context(CONTEXT_USER, $user->id);
    require_once $CFG->dirroot . '/tag/lib.php';
    tag_set('user', $user->id, array());
    // workaround for bulk deletes of users with the same email address
    $delname = addslashes("{$user->email}." . time());
    while (record_exists('user', 'username', $delname)) {
        // no need to use mnethostid here
        $delname++;
    }
    // mark internal user record as "deleted"
    $updateuser = new object();
    $updateuser->id = $user->id;
    $updateuser->deleted = 1;
    $updateuser->username = $delname;
    // Remember it just in case
    $updateuser->email = md5($user->username);
    // Store hash of username, useful importing/restoring users
    $updateuser->idnumber = '';
    // Clear this field to free it up
    $updateuser->timemodified = time();
    if (update_record('user', $updateuser)) {
        commit_sql();
        // notify auth plugin - do not block the delete even when plugin fails
        $authplugin = get_auth_plugin($user->auth);
        $authplugin->user_delete($user);
        events_trigger('user_deleted', $user);
        return true;
    } else {
        rollback_sql();
        return false;
    }
}

//.........这里部分代码省略.........
     $fresult = array();
     foreach ($contexts as $context) {
         $context = trim($context);
         if (empty($context)) {
             continue;
         }
         begin_sql();
         if ($this->config->search_sub) {
             //use ldap_search to find first user from subtree
             $ldap_result = ldap_search($ldapconnection, $context, $filter, array($this->config->user_attribute));
         } else {
             //search only in this context
             $ldap_result = ldap_list($ldapconnection, $context, $filter, array($this->config->user_attribute));
         }
         if ($entry = ldap_first_entry($ldapconnection, $ldap_result)) {
             do {
                 $value = ldap_get_values_len($ldapconnection, $entry, $this->config->user_attribute);
                 $value = $textlib->convert($value[0], $this->config->ldapencoding, 'utf-8');
                 // usernames are __always__ lowercase.
                 array_push($fresult, moodle_strtolower($value));
                 if (count($fresult) >= $bulk_insert_records) {
                     $this->ldap_bulk_insert($fresult, $temptable);
                     $fresult = array();
                 }
             } while ($entry = ldap_next_entry($ldapconnection, $entry));
         }
         unset($ldap_result);
         // free mem
         // insert any remaining users and release mem
         if (count($fresult)) {
             $this->ldap_bulk_insert($fresult, $temptable);
             $fresult = array();
         }
         commit_sql();
     }
     /// preserve our user database
     /// if the temp table is empty, it probably means that something went wrong, exit
     /// so as to avoid mass deletion of users; which is hard to undo
     $count = get_record_sql('SELECT COUNT(username) AS count, 1 FROM ' . $temptable);
     $count = $count->{'count'};
     if ($count < 1) {
         print "Did not get any users from LDAP -- error? -- exiting\n";
         exit;
     } else {
         print "Got {$count} records from LDAP\n\n";
     }
     /// User removal
     // find users in DB that aren't in ldap -- to be removed!
     // this is still not as scalable (but how often do we mass delete?)
     if (!empty($this->config->removeuser)) {
         $sql = "SELECT u.id, u.username, u.email, u.auth \n                    FROM {$CFG->prefix}user u\n                        LEFT JOIN {$temptable} e ON u.username = e.username\n                    WHERE u.auth='ldap'\n                        AND u.deleted=0\n                        AND e.username IS NULL";
         $remove_users = get_records_sql($sql);
         if (!empty($remove_users)) {
             print "User entries to remove: " . count($remove_users) . "\n";
             foreach ($remove_users as $user) {
                 if ($this->config->removeuser == 2) {
                     if (delete_user($user)) {
                         echo "\t";
                         print_string('auth_dbdeleteuser', 'auth', array($user->username, $user->id));
                         echo "\n";
                     } else {
                         echo "\t";
                         print_string('auth_dbdeleteusererror', 'auth', $user->username);
                         echo "\n";
                     }
                 } else {

function stats_upgrade_for_roles_wrapper()
{
    global $CFG;
    if (!empty($CFG->statsrolesupgraded)) {
        return true;
    }
    $result = begin_sql();
    $result = $result && stats_upgrade_user_table_for_roles('daily');
    $result = $result && stats_upgrade_user_table_for_roles('weekly');
    $result = $result && stats_upgrade_user_table_for_roles('monthly');
    $result = $result && stats_upgrade_table_for_roles('daily');
    $result = $result && stats_upgrade_table_for_roles('weekly');
    $result = $result && stats_upgrade_table_for_roles('monthly');
    $result = $result && commit_sql();
    if (!empty($result)) {
        set_config('statsrolesupgraded', time());
    }
    // finally upgade totals, no big deal if it fails
    stats_upgrade_totals();
    return $result;
}

/**
 * Actual implementation of the rest coures functionality, delete all the
 * quiz attempts for course $data->courseid, if $data->reset_quiz_attempts is
 * set and true.
 *
 * Also, move the quiz open and close dates, if the course start date is changing.
 *
 * @param $data the data submitted from the reset course forum.
 * @param $showfeedback whether to output progress information as the reset
 *      progresses.
 */
function quiz_delete_userdata($data, $showfeedback = true)
{
    global $CFG;
    /// Delete attempts.
    if (!empty($data->reset_quiz_attempts)) {
        $conditiononquizids = 'quiz IN (SELECT id FROM ' . $CFG->prefix . 'quiz q WHERE q.course = ' . $data->courseid . ')';
        $attemptids = get_records_select('quiz_attempts', $conditiononquizids, '', 'id, uniqueid');
        if ($attemptids) {
            if ($showfeedback) {
                echo '<div class="notifysuccess">', get_string('deletingquestionattempts', 'quiz');
                $divider = ': ';
            }
            foreach ($attemptids as $attemptid) {
                delete_attempt($attemptid->uniqueid);
                if ($showfeedback) {
                    echo $divider, $attemptid->uniqueid;
                    $divider = ', ';
                }
            }
            if ($showfeedback) {
                echo "</div><br />\n";
            }
        }
        if (delete_records_select('quiz_grades', $conditiononquizids) && $showfeedback) {
            notify(get_string('gradesdeleted', 'quiz'), 'notifysuccess');
        }
        if (delete_records_select('quiz_attempts', $conditiononquizids) && $showfeedback) {
            notify(get_string('attemptsdeleted', 'quiz'), 'notifysuccess');
        }
    }
    /// Update open and close dates
    if (!empty($data->reset_start_date)) {
        /// Work out offset.
        $olddate = get_field('course', 'startdate', 'id', $data->courseid);
        $olddate = usergetmidnight($olddate);
        // time part of $olddate should be zero
        $newdate = make_timestamp($data->startyear, $data->startmonth, $data->startday);
        $interval = $newdate - $olddate;
        /// Apply it to quizzes with an open or close date.
        $success = true;
        begin_sql();
        $success = $success && execute_sql("UPDATE {$CFG->prefix}quiz\n                    SET timeopen = timeopen + {$interval}\n                    WHERE course = {$data->courseid} AND timeopen <> 0", false);
        $success = $success && execute_sql("UPDATE {$CFG->prefix}quiz\n                    SET timeclose = timeclose + {$interval}\n                    WHERE course = {$data->courseid} AND timeclose <> 0", false);
        if ($success) {
            commit_sql();
            if ($showfeedback) {
                notify(get_string('openclosedatesupdated', 'quiz'), 'notifysuccess');
            }
        } else {
            rollback_sql();
        }
    }
}

//.........这里部分代码省略.........
         echo "Searching Context: " . $context . "\n";
         begin_sql();
         if ($this->config->search_sub) {
             //use ldap_search to find first user from subtree
             $ldap_result = ldap_search($ldapconnection, $context, $filter, array($this->config->user_attribute));
         } else {
             //search only in this context
             $ldap_result = ldap_list($ldapconnection, $context, $filter, array($this->config->user_attribute));
         }
         if ($entry = ldap_first_entry($ldapconnection, $ldap_result)) {
             do {
                 $value = ldap_get_values_len($ldapconnection, $entry, $this->config->user_attribute);
                 $value = $textlib->convert($value[0], $this->config->ldapencoding, 'utf-8');
                 // usernames are __always__ lowercase.
                 if (strpos($value[0], '$') && $this->config->user_type == 'ad') {
                     // Eliminiate AD Service Accounts
                     continue;
                 }
                 // Skip AD Service Account Entries
                 array_push($fresult, moodle_strtolower($value));
                 if (count($fresult) >= $bulk_insert_records) {
                     $this->ldap_bulk_insert($fresult, $temptable);
                     $fresult = array();
                 }
             } while ($entry = ldap_next_entry($ldapconnection, $entry));
         }
         unset($ldap_result);
         // free mem
         // insert any remaining users and release mem
         if (count($fresult)) {
             $this->ldap_bulk_insert($fresult, $temptable);
             $fresult = array();
         }
         commit_sql();
     }
     /// preserve our user database
     /// if the temp table is empty, it probably means that something went wrong, exit
     /// so as to avoid mass deletion of users; which is hard to undo
     $count = get_record_sql('SELECT COUNT(username) AS count, 1 FROM ' . $temptable);
     $count = $count->{'count'};
     if ($count < 1) {
         print "Did not get any users from LDAP -- error? -- exiting\n";
         exit;
     } else {
         print "Got {$count} records from LDAP\n\n";
     }
     /// User removal
     // find users in DB that aren't in ldap -- to be removed!
     // this is still not as scalable (but how often do we mass delete?)
     if (!empty($this->config->removeuser)) {
         $sql = "SELECT u.id, u.username, u.email, u.auth\r\n                    FROM {$CFG->prefix}user u\r\n                       LEFT JOIN {$temptable} e ON u.username = e.username\r\n                       AND u.mnethostid = e.mnethostid\r\n                    WHERE u.auth='ldapsso'\r\n                        AND u.deleted=0\r\n                        AND e.username IS NULL";
         $remove_users = get_records_sql($sql);
         if (!empty($remove_users)) {
             print "User entries to remove: " . count($remove_users) . "\n";
             foreach ($remove_users as $user) {
                 if ($this->config->removeuser == 2) {
                     if (delete_user($user)) {
                         echo "\t";
                         print_string('auth_dbdeleteuser', 'auth', array($user->username, $user->id));
                         echo "\n";
                     } else {
                         echo "\t";
                         print_string('auth_dbdeleteusererror', 'auth', $user->username);
                         echo "\n";
                     }
                 } else {

function dialogue_delete_conversation($dialogueid, $conversationid)
{
    //echo "<div style=\"text-align:center;\">deleting dialogue $dialogueid and conversation $conversationid</div>";
    begin_sql();
    //$tx = true; // transaction sanity
    $tx = delete_records("dialogue_conversations", "id", $conversationid, "dialogueid", $dialogueid);
    $tx = $tx && delete_records("dialogue_entries", "conversationid", $conversationid, "dialogueid", $dialogueid);
    if ($tx) {
        commit_sql();
    } else {
        rollback_sql();
        error("oups...error deleting conversation");
        return false;
    }
    return true;
}

/**
 * Process Job's results logged in a text file.
 * 
 * @param array $scan from table blended_scans
 */
function register_scannedjob($scan)
{
    global $CFG;
    global $scansfoldername;
    $jobid = $scan->id;
    $fieldspath = blended_getOMRFieldsetDir($scan);
    $logfile = blended_getOMRInputLogFilePath($scan);
    try {
        if ($logfile != 'null') {
            $logelements = read_log_file($logfile);
        }
        if (!isset($logelements) || count($logelements) == 0) {
            throw new OMRError("Log file is empty", OMRError::LOG_FILE_IS_EMPTY);
        }
    } catch (OMRError $e) {
        throw $e;
    }
    // open a transaction
    begin_sql();
    foreach ($logelements as $logelement) {
        try {
            //cada elemento es un registro de blended_images.
            $image_result = parse_log_elements($logelement);
            $image_result->jobid = $jobid;
            register_image($image_result);
            $acode = $image_result->activitycode;
            if ($acode != null) {
                if ($acode == 'Undetected') {
                    mtrace("Undetected activity code for result:" . $logelement);
                } else {
                    mtrace('<br>REGISTERING FIELDS...');
                    register_template_fields($image_result, $fieldspath);
                    mtrace('<br>REGISTERING RESULTS...');
                    register_result_files($image_result, $fieldspath);
                    mtrace('<br>CHECKING VALIDITY...');
                    check_invalid_results($image_result);
                }
            }
        } catch (Exception $e) {
            mtrace('OMRError: ' . $e->getMessage());
            register_exception($e, $jobid);
            $errorcode = $e->getCode();
            if ($errorcode == 5 or $errorcode == 6) {
                //print_object($e);
                //throw $e;
                continue;
                // process next result
            }
        }
    }
    mtrace('<br>UPDATING SCANJOB QUEUE...');
    update_record('blended_scans', $scan);
    // End the transaction
    commit_sql();
    return;
}

//.........这里部分代码省略.........
        /// Entries for the log_display table
        $success = $success && modify_database('', " INSERT INTO prefix_log_display (module, action, mtable, field) VALUES ('quiz', 'preview', 'quiz', 'name');");
        $success = $success && modify_database('', " INSERT INTO prefix_log_display (module, action, mtable, field) VALUES ('quiz', 'start attempt', 'quiz', 'name');");
        $success = $success && modify_database('', " INSERT INTO prefix_log_display (module, action, mtable, field) VALUES ('quiz', 'close attempt', 'quiz', 'name');");
        /// update the default settings in $CFG
        $review = QUIZ_REVIEW_IMMEDIATELY & QUIZ_REVIEW_RESPONSES + QUIZ_REVIEW_SCORES;
        if (!empty($CFG->quiz_feedback)) {
            $review += QUIZ_REVIEW_IMMEDIATELY & QUIZ_REVIEW_FEEDBACK;
        }
        if (!empty($CFG->quiz_correctanswers)) {
            $review += QUIZ_REVIEW_IMMEDIATELY & QUIZ_REVIEW_ANSWERS;
        }
        if (isset($CFG->quiz_review) and $CFG->quiz_review & 1) {
            $review += QUIZ_REVIEW_CLOSED;
        }
        if (isset($CFG->quiz_review) and $CFG->quiz_review & 2) {
            $review += QUIZ_REVIEW_OPEN;
        }
        $success = $success && set_config('quiz_review', $review);
        /// Use tolerance instead of min and max in numerical question type
        $success = $success && table_column('quiz_numerical', '', 'tolerance', 'varchar', '255', '', '0.0', 'not null', 'question');
        $success = $success && execute_sql("UPDATE {$CFG->prefix}quiz_numerical SET tolerance = (max::text::real-min::text::real)/2");
        $success = $success && modify_database('', 'ALTER TABLE prefix_quiz_numerical DROP COLUMN min');
        // Replaced by tolerance
        $success = $success && modify_database('', 'ALTER TABLE prefix_quiz_numerical DROP COLUMN max');
        // Replaced by tolerance
        /// Tables for Remote Questions
        $success = $success && modify_database('', "CREATE TABLE prefix_quiz_rqp (\n                                 id SERIAL PRIMARY KEY,\n                                 question integer NOT NULL default '0',\n                                 type integer NOT NULL default '0',\n                                 source text NOT NULL,\n                                 format varchar(255) NOT NULL default '',\n                                 flags integer NOT NULL default '0',\n                                 maxscore integer NOT NULL default '1'\n                               );");
        $success = $success && modify_database('', "CREATE INDEX prefix_quiz_rqp_question_idx ON prefix_quiz_rqp (question);");
        $success = $success && modify_database('', "CREATE TABLE prefix_quiz_rqp_states (\n                                 id SERIAL PRIMARY KEY,\n                                 stateid integer NOT NULL default '0',\n                                 responses text NOT NULL,\n                                 persistent_data text NOT NULL,\n                                 template_vars text NOT NULL\n                               );");
        $success = $success && modify_database('', "CREATE TABLE prefix_quiz_rqp_types (\n                                id SERIAL PRIMARY KEY,\n                                name varchar(255) NOT NULL default '',\n                                rendering_server varchar(255) NOT NULL default '',\n                                cloning_server varchar(255) NOT NULL default '',\n                                flags integer NOT NULL default '0'\n                              );");
        $success = $success && modify_database('', "CREATE UNIQUE INDEX prefix_quiz_rqp_types_name_uk ON prefix_quiz_rqp_types (name);");
        if ($success) {
            $success = $success && commit_sql();
        } else {
            rollback_sql();
        }
    }
    if ($success && $oldversion < 2005042900 && false) {
        // We don't want this to be executed any more!!!
        begin_sql();
        $success = $success && table_column('quiz_multianswers', '', 'sequence', 'varchar', '255', '', '', 'not null', 'question');
        $success = $success && table_column('quiz_numerical', '', 'answers', 'varchar', '255', '', '', 'not null', 'answer');
        $success = $success && modify_database('', 'UPDATE prefix_quiz_numerical SET answers = answer');
        $success = $success && table_column('quiz_questions', '', 'parent', 'integer', '10', 'unsigned', '0', 'not null', 'category');
        $success = $success && modify_database('', "UPDATE prefix_quiz_questions SET parent = id WHERE qtype ='" . RANDOM . "';");
        // convert multianswer questions to the new model
        if ($multianswers = get_records_sql("SELECT m.id, q.category, q.id AS parent,\n                                        q.name, q.questiontextformat, m.norm AS\n                                        defaultgrade, m.answertype AS qtype,\n                                        q.version, q.hidden, m.answers,\n                                        m.positionkey\n                                        FROM {$CFG->prefix}quiz_questions q,\n                                             {$CFG->prefix}quiz_multianswers m\n                                        WHERE q.qtype = '" . MULTIANSWER . "'\n                                        AND   q.id = m.question\n                                        ORDER BY q.id ASC, m.positionkey ASC")) {
            $multianswers = array_values($multianswers);
            $n = count($multianswers);
            $parent = $multianswers[0]->parent;
            $sequence = array();
            // turn reporting off temporarily to avoid one line output per set_field
            $olddebug = $db->debug;
            $db->debug = false;
            for ($i = 0; $i < $n; $i++) {
                $answers = $multianswers[$i]->answers;
                unset($multianswers[$i]->answers);
                $pos = $multianswers[$i]->positionkey;
                unset($multianswers[$i]->positionkey);
                // create questions for all the multianswer victims
                unset($multianswers[$i]->id);
                $multianswers[$i]->length = 0;
                $multianswers[$i]->questiontext = '';
                $multianswers[$i]->stamp = make_unique_id_code();
                $id = insert_record('quiz_questions', $multianswers[$i]);